1. Field of the Invention
The present invention relates to a gas discharge display device such as a surface discharge type plasma display panel (PDP) utilizing a light emission device.
A PDP has been becoming widespread as a television set having a large screen taking advantage of commercialization of a color display. One of tasks concerning the image quality of a PDP is to enlarge a reproducible color range.
2. Description of the Prior Art
As a conventional color display device, an AC type PDP having a three-electrode surface discharge structure is commercialized. This PDP has a pair of main electrodes arranged in parallel for sustaining of each line (row) of matrix display and an address electrode arranged for each column, so that total three electrodes are used for a cell that is a unit of light emission element. In the surface discharge structure, the main electrode pair is arranged on a first substrate, and a fluorescent material layer for color display is arranged on a second substrate opposing the first substrate. Thus, deterioration of the fluorescent material layer due to the impact of ion upon discharge can be reduced and a long life of PDP can be realized.
In the color display, three cells correspond to each pixel of an image. A display color of each pixel is determined by controlling a light emission quantity of the fluorescent material of each color, i.e., red, green or blue color. Conventionally, the composition of fluorescent materials and the light emission intensity ratio of three colors are selected so that the display color becomes white when the light emission quantity is the maximum in the variable range for each of red, green and blue colors.
It is difficult to prevent the light emission color of a discharge gas from mixing with the light emission color of the fluorescent material in a color display utilizing a gas discharge. The light emission of the discharge gas can deteriorate color reproducibility of a PDP.
FIG. 12 shows a light emission spectrum of a two-component gas containing neon (Ne) and xenon (Xe). An example of a light emission peak of each fluorescent material of red, green and blue colors in a broken line in FIG. 12. As understood from FIG. 12, the light emission peak of the discharge gas is at the vicinity of the maximum light emission peak (585 nm) of the red fluorescent material. This is cased by the neon gas component of the discharge gas. Despite the reproduced color of the fluorescent material, a reddish display is obtained over the entire screen since the red color of the light emission of the neon gas is added. Thus, a color purity of each of the red, green and blue colors is deteriorated. Especially, the display ability of blue color is deteriorated. In addition, the display color of white color pixel may have a low color temperature value compared with the reproduced color of each fluorescent material.